Non-slipping tread.



UMTED saJATns PATENT OFFICE,

FRANK H, STANWOOD, 0F ARLINGTON, MASSACHUSETTS, ASSIGINOR T0 STANWOOD EQUIPMENT COMPANY, A CORPORATION .OF MAINE,

NON-SLIPPING TREAD.

Specicatinn o! Letters Patent.

Patented Feb. 19, 1918.

Application led `lane 14', 1916. Serial No. 103,005.

State of Massachusetts, have invented a new and useful Improvement in Non-Slipping Trends, of which the following is a speciticationA This invention relates in general to non slipping treads adapted for use in tread or working surfaces, such as stair steps, walks, runways and the like, a particular use of the invention, however. being in connectionr with e, r ming boards for automobiles and o; v-. ,.'cles, although it will be manifest as the invention is better understood that it has a much wider and broader application.

' A principal object of this invention is the provision of a non-slipping tread for automobiles and the like which may be supplied to the automobile maker or user in units ready for instant application requiring only the fastening of the unit in desired location.

A further object of the invention is the provision of such an article which will consist essentially of a central or body sheet of metal coated with a non-slipping ribbed surface so united with a central body sheet as to restrain any movement of the nonslipping coating in service, the union between the body or central sheet and the coating being so produced as to 'redue the wearing of the coating material to a minimum'.

Other objects and advantages of the invention will be apparent as it is better understood from the following description when considered in connection with the accompanying drawing illustrating a pre- -ferred embodiment thereof.

0n the drawing,

Figure 1 is aperspective view 'of a nonslipping tread embodying my present invention;

Fig. '2 is a bottom plan view of the same with a part of the coating broken away;

Fi 3 is a section taken on the line 3-3 of Fig. 1;

Fig. 4 is a section on the line l1--4 of Fig. 1.

For the purpose of illustrating my present invention, I have shown on the drawing a non-slipping tread -which is comprised of a central metal body sheet' coated with a non-slipping composition, preferably rubber as will be now described. The sheet 6 is provided with apertures 7` through which screws, rivets or other fastening means may be inserted, and is otherwise preferably imperforate. The coating of nonslip material is molded about the sheet and is formed to provide two series of elongated parallel upwardly extending ribs 8. The material of the coating 8 extends completely about the body sheet 6 forming a layer 9 beneath it, inclosing its edges at 10 and covering its upper face to provide the parallelly extend,- ing ribs 8. The ribs 8 are preferably arranged in two parallclly extending series each composed of ribs extending from an end of the plate inwardlv to adjacent its transverse center in parallelism.

The plate 6 is coated with a material which will cause the rubber or other composition to be secured firmly to the plate throughout the contacting area. of the two materials. The internal or securing coating is preferably of some chemical composition containing copper which has a marked atlinity for the iron of the plate and the rubber of thc composition. A substance well designed to accomplish the purposes of my present invention is copper sulfate, which is preferably lightly painted with a' brush or otherwise upon the plate. In practice as little as possible of this sulfate is used, indeed` in the finished plate preferably no copper or copper sulfate is visible, the intermediate holding material merely apparently soiling the plate. By its use mechanical interlocking of the rubbei' and metal is rendered unnecessary and the pressure felt bythe tread pads or ribs 8 is transmitted against. the smooth upper surface of the plate without encountering any edges, corners or projections 'of the `plate which would tend to cut into the rub- Cri The eoatin of the plate permitsV ol?. use of relatively 1% ribs sinee the connection thus providedff'be tween the ribs und the plate is snllieient to prevent the ribs bending over and tearing away.

The 'plate coated with green or nnvnleanized rubber is placed in a mold' and` suitable pilotel or pins extend through thty opening 7 to prevent their closure by the rubber. The heat is then applied and the rubber vulcanized to the plate by reason of the presence of the Copper in the internal Securing coating.

It is thought that the invention and many of its attendant advantages will be apparent from the foregoiilg without further description, and it will be obvious that vari ons changesmay be made in the form of the article and in the, ilori'n and et'nistnuction and arrangement' of its parts without cleparting from the spirit of the inventionn or sacrificing any of its material advantages,

in rubber portions between the the form hereinbelore described being merely a. preferred embodiment thereof.

I claim:

A non-slipping (read comprising an internal meta plattl and a covering of ri1bbe above. and beneath said plate and vnl eanized thereto, the portion 0l' the covering above said plate having npstanding iso lated ribsl eoiineeted at their bases by th(l Upper parly ol I#aid Covering the latter adhering by said vnleani'nnlion to the (op ol' the plate between the ribs, the vnleanization of the material ol" the covering beneath said ribs and between said ribs and the material of the verering between Said ribs serving together to restrain the ribs :igainet displacement in service.

Signed in the presence of two subserib ing witnesses.

FRANK lll. STANVVOOD. Witnesses: 

